So far I'm liking 4.1
ZA and ZG are nice rehashes. Some people don't like recycled content but I think its fun to go back through places you know and experience them in a new way. Most of the bosses seem really difficult at first until you understand the mechanics. Then they're pretty easy. They want these two zones to gear people up item-wise and skill-wise for raiding. Several of them have abilities very similar to raid bosses.
The only thing I don't like about this patch is they took away my cash cow
I used to buy gems and ores under a certain price and cut them to resell to a vendor for 9g. Now they made the cut gems value only 75s!!! So now I have to find something else. Rare quality red color gems (Inferno Ruby) have been inflated pretty high on our server so I'm making a little bit of money off those. But otherwise there's nothing as easy as it was to buy, cut, and vendor the green quality gems :(